Flagger on Konvoy

Flagger helps automate the release process for Kubernetes workloads with a custom resource named canary. It depends on serive-mesh technology to handle advanced deployment strategies, However it can also work with Nginx Ingress controllers however it would be restricted to the a limited number of deployment strategies. In this demo we will walk through installing and configuring on Konvoy Kubernetes cluster

Prerequisites

1. Flagger requires a Kubernetes v1.14 or higher
2. Konvoy v1.4 or higher
3. Istio enbled in Konvoy cluster
4. Prometheus running as metrics-server in kubeaddons namespace
5. Privilege access to the Konvoy cluster

Install Flagger

1. Modify the cluster.yaml file so that flagger is enable by changing it to true from false

......
        - name: flagger
          enabled: true    <--- change this line to true from the default of false

2. Install Flagger by using Konvoy

konvoy deploy addons --yes

This would review all the enabled addons and deploy them as necessary.

Output:

STAGE [Deploying Enabled Addons]
external-dns                                                           [OK]
dashboard                                                              [OK]
reloader                                                               [OK]
konvoyconfig                                                           [OK]
opsportal                                                              [OK]
cert-manager                                                           [OK]
gatekeeper                                                             [OK]
defaultstorageclass-protection                                         [OK]
traefik                                                                [OK]
awsebscsiprovisioner                                                   [OK]
istio                                                                  [OK]
dex                                                                    [OK]
kube-oidc-proxy                                                        [OK]
traefik-forward-auth                                                   [OK]
dex-k8s-authenticator                                                  [OK]
prometheus                                                             [OK]
prometheusadapter                                                      [OK]
velero                                                                 [OK]
elasticsearch                                                          [OK]
elasticsearch-curator                                                  [OK]
fluentbit                                                              [OK]
elasticsearchexporter                                                  [OK]
kibana                                                                 [OK]
kommander                                                              [OK]

Kubernetes cluster and addons deployed successfully!

3. Lets ensure that Flagger was deployed successfully without any challenges

kubectl get deploy,po -n istio-system

Output:

NAME                                   READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/flagger                1/1     1            1           60s
deployment.apps/istio-ingressgateway   2/2     2            2           3d6h
deployment.apps/istio-operator         1/1     1            1           3d6h
deployment.apps/istio-tracing          1/1     1            1           3d6h
deployment.apps/istiod                 2/2     2            2           3d6h
deployment.apps/kiali                  1/1     1            1           3d6h

NAME                                        READY   STATUS      RESTARTS   AGE
pod/flagger-58b69886f8-xb69d                1/1     Running     0          60s
pod/istio-crd-1.6.4-udb5r-gqzcm             0/1     Completed   0          3d6h
pod/istio-ingressgateway-59ddcb9559-bvnwg   1/1     Running     0          3d6h
pod/istio-ingressgateway-59ddcb9559-s9dqx   1/1     Running     0          3d6h
pod/istio-operator-65458b9b8b-wwbg6         1/1     Running     0          3d6h
pod/istio-tracing-dbfcd555-m8h7n            1/1     Running     0          3d6h
pod/istiod-59ddb865bb-8l2c2                 1/1     Running     0          3d6h
pod/istiod-59ddb865bb-qz47z                 1/1     Running     0          3d6h
pod/kiali-6f9b78cdc6-wtmdl                  1/1     Running     0          3d6h

Notice that Flagger, Deployment and Pod running successfully.

4. Review logs for Flagger pod to ensure that there are no errors.

kubectl logs pod/flagger-58b69886f8-xb69d -n istio-system

Output:

{"level":"info","ts":"2020-08-20T21:51:36.684Z","caller":"flagger/main.go:112","msg":"Starting flagger version 1.1.0 revision b6d6f32c7f6377e837788db7f7fdb49a25fda057 mesh provider istio"}
{"level":"info","ts":"2020-08-20T21:51:36.699Z","caller":"flagger/main.go:383","msg":"Connected to Kubernetes API v1.17.8"}
{"level":"info","ts":"2020-08-20T21:51:36.699Z","caller":"flagger/main.go:239","msg":"Waiting for canary informer cache to sync"}
{"level":"info","ts":"2020-08-20T21:51:36.799Z","caller":"flagger/main.go:246","msg":"Waiting for metric template informer cache to sync"}
{"level":"info","ts":"2020-08-20T21:51:36.899Z","caller":"flagger/main.go:253","msg":"Waiting for alert provider informer cache to sync"}
{"level":"info","ts":"2020-08-20T21:51:37.007Z","caller":"flagger/main.go:163","msg":"Connected to metrics server http://prometheus-kubeaddons-prom-prometheus.kubeaddons:9090"}
{"level":"info","ts":"2020-08-20T21:51:37.008Z","caller":"server/server.go:29","msg":"Starting HTTP server on port 8080"}
{"level":"info","ts":"2020-08-20T21:51:37.008Z","caller":"controller/controller.go:164","msg":"Starting operator"}
{"level":"info","ts":"2020-08-20T21:51:37.008Z","caller":"controller/controller.go:173","msg":"Started operator workers"}

Note This ensure that Flagger was able to communicate with the Prometheus Metrics server without any issues. This is very important as Flagger depends on the metrics-server to perform most of its functions. If flagger is unable to communicate with metrics-server rest of the demo would not go as intended.